Multispectral imaging can provide spatial and spectral information about samples and scenes, so that each pixel in an image can be described in terms of its optical spectrum. As a result, spectral analysis of such images can yield valuable information about the composition, appearance, and other aspects of a sample.
A multispectral dataset can be considered to have the form of an image cube, with two spatial dimensions and one spectral dimension. Various instruments have been devised to acquire spectral image cubes, and these can be grouped according to how they acquire data: point-sequential spectral (PSS) systems; line-sequential spectral (LSS) systems; imaging interferogram (IIF) systems; and band-sequential image (BSI) systems. The latter systems incorporate a wavelength-selection element such as a tunable filter or filter wheel, along with an imaging detector.